Radial engines are just plain cool – it’s inarguable that any tech that originated with early aviation is inherently awesome. But, what do you do when you want to build a radial engine in your dorm where a combustion engine would be inadvisable? For University of Washington students [Jeffrey Weng] and [Connor Lee] the answer was to power it with solenoids in place of the pistons.
The easiest way to approach a project like this would have been to use a microcontroller. A simple program running on an Arduino could have easily provided the timing to switch power to each solenoid in succession. [Jeffrey Weng] and [Connor Lee], however, took a much more interesting approach by controlling timing via a simple distributor. This works in the same way a spark distributor on a combustion engine would have worked, except it’s actually providing the power to actuate the solenoids instead of providing just an ignition spark.
Also impressive is what they were able to accomplish with such basic tools. Those of us who are lazy and have access to more expensive tools would have just 3D printed or CNC cut most of the parts. Either [Jeffrey Weng] and [Connor Lee] didn’t have access to these, or they wanted to increase their machining street cred, because they created all of the parts with simple tools like a band saw and drill press. We’ve seen some beautiful engine projects before, but what this build lacks in objective beauty it makes up for in ingenuity.
Continue reading “Radial Solenoid Engine is Undeniably Cool”
There are many different ways to keep your plants watered on a schedule. [Luca Dentella] just created a new one by building the irrighino watering system. He used standard off the shelf, hardware to keep it simple. Irrighino is a complete watering system based on the Arduino Yun, featuring a user friendly AJAX interface. This allows scheduling in a manner similar to creating appointments in Outlook. It’s also possible to manually control the various water solenoids. The code is fully customizable and open source, with code available from [Luca’s] github repository. The web interface is divided in to three tabs – “runtime” for manual control, “setup” to configure the scheduling, and “events” to view system logs.
The Arduino Yun activates solenoid valves via a relay shield. A switch panel has indicator Status LED’s and three position switches. These allow the outputs to be switched off or on manually, or controlled via the Yun when in auto mode. [Luca] describes how to read three states of the switch (On-Off-On) when connected to a single analog input of the Arduino. He’s also got another tutorial describing how to connect a USB WiFi adapter to the Yun. This is handy since the Yun is mounted inside an enclosure where the signal strength is very weak. While the Yun has on-board WiFi, there is no possibility to attach an external antenna directly to the test SMA socket.
One interesting part is the commercial rain sensor. It’s a switch surrounded by a spongy material. When this material absorbs rain water, it begins to expand and triggers the switch. The Arduino sees the sensor as a simple digital input.
Check a short demo of his system in the video after the break.
Continue reading “Irrighino, an Arduino Yun Based Watering System”
[Kirk Kaiser] isn’t afraid to admit his latest project a bit strange, being a plant-controlled set of robotic bongos. We don’t find it odd at all. This is the kind of thing we love to see. His project’s origins began a month ago after taking a class at NYC Resistor about creating music from robotic instruments. Inspired to make his own, [Kirk] repurposed a neighbor’s old wooden dish rack to serve as a mount for solenoids that, when triggered, strike a couple of plastic cowbells or bongo drums.
A Raspberry Pi was originally used to interface the solenoids with a computer or MIDI keyboard, but after frying it, he went with a Teensy LC instead and never looked back. Taking advantage of the Teensy’s MIDI features, [Kirk] programmed a specific note to trigger each solenoid. When he realized that the Teensy also had capacitive touch sensors, he decided to get his plants in on the fun in a MaKey MaKey kind of way. Each plant is connected to the Teensy’s touchRead pins by stranded wire; the other end is stripped, covered with copper tape, and placed into the soil. When a plant’s capacitance surpasses a threshold, the respective MIDI note – and solenoid – is triggered. [Kirk] quickly discovered that hard-coding threshold values was not the best idea. Looking for large changes was a better method, as the capacitance was dramatically affected when the plant’s soil dried up. As [Kirk] stood back and admired his work, he realized there was one thing missing – lights! He hooked up an Arduino with a DMX shield and some LEDs that light up whenever a plant is touched.
We do feel a disclaimer is at hand for anyone interested in using this botanical technique: thorny varieties are ill-advised, unless you want to play a prank and make a cactus the only way to turn the bongos off!
Continue reading “Play Robotic Bongos using your Household Plants”
Remember those childhood memories of your grandmother telling you to stop hammering away at her pots and pans? Odds are pretty good that the last time you struck a beat with her dishware, you had a few more years to go before you understood tempo and rhythm. Now that we’re a bit older, [Jiffer Harriman] invites us to return to our kitchen armed not only with those childhood memories, but also a with the Kitsch-Instrument: a suite of solenoids, a controller, and a software pipeline to algorithmically turn your kitchen into a giant percussion instrument.
The Kitsch-Instrument is a modular music system that enables the user to pull a percussive pattern out of his or her everyday kitchen utensils. The percussion hits come from a series of mosfet-driven solenoids that can be fixed onto plates, cups, and other everyday items through a variety of clips. These solenoids are collectively driven by two stacked custom Arduino shields that are, in turn, driven either by hand with a button-interface, or algorithmically with a pattern generated by the graphical programming language, Pure Data.
In designing this project, [Jiffer] and his team intended to bring not just a musical tool to young tinkerers. They also aimed to help educate these young minds with multiple entry points into their project. For top-level users, adding buttons is almost as easy as plug-in-and-play. For experienced circuit designers and tinkerers, the entire project is open source with the board layout and software available for download. Overall the project can be explored from lower and lower levels while still retaining its functionality as a musical interface.
If you suspect that this project seems to have that same whimsical sense as the Auto-Meter-Reader Feeder, you’d be right! [Jiffer] and [Zack] hail from the same lab at the University of Colorado. We’re excited to see what upcoming beats will arise from a truly off-the-shelf symphony.
via the [Tangible Embedded and Embodied Conference]
Continue reading “Kitsch-Instrument Pulls a Sonata out of your Dishware”
Just about all of us have a few old hard drives in our junk box. There are a myriad of projects out there to put them to work in new and interesting ways. One of those ways is to turn your hard drive into a solenoid motor of sorts. (YouTube link) This isn’t a new hack, videos of it have been kicking around the internet for years. [black1985vette] gives a pretty good explanation of how he’s done it. He used a piece of brass as a connecting rod between the drive head and a pin mounted off-center to the platter hub. One of the platter mounting screws provides the perfect place to set the pin. A bent safety-pin rubs the center of the hub, which is partially insulated with tape. When the pin contacts the hub, the drive head is energized, pushing the whole assembly around. The mass of the platters acts as a flywheel, carrying the motor the rest of the way around.
[Pulverrostmannen] performed a similar mod, though he used a micro switch to time the drive head. Rather than a brass connecting rod, [Pulverrostmannen] used a spare head. With a simple transistor circuit acting as a speed control, his hard drive motor revved up to around 1560 RPM, which is pretty respectable for a bunch of junk parts.
So next time you’re stuck in on cold rainy weekend, pull out some of those old drives and get hacking! Click past the break to several of these projects in action.
Continue reading “Spin up an old hard drive with a solenoid motor”
Planting your car just about anywhere almost always comes at a price; and, if you’re overdue for your return, odds are good that you’ll end up paying a much steeper price than intended. Parking meters are wonderful devices at telling the authorities just how much time you have left until you’re ticketworthy. [Zack] figured that five–even ten minutes late—is an absurd reason to pay a fine, so he’s developed a tool that will preload a meter with a few extra coins when the authorities get too close.
The law-enforcement detection system puts together of number of tools and techniques that we’re intimately familiar with: 3D printing, Arduino, a photoresistor, and a proximity (PIR) sensor. At the code level, [Zack] filters his analog photo resistor with a rolling average to get a clean signal that triggers both by day and by night. The trigger? Two possibilities. The PIR sensor detects curious law enforcement officers while the filtered photoresistor detects the periodic twirling siren lights. Both events will energize a solenoid to drop a few extra coins through a slide and into the meter slot.
For a collection of well-known components, [Zack] could’ve packed his contraption into a Altoids Tin and called it a day. Not so. As an interaction designer, looks could make or break the experience. For this reason, he opts for a face-hugging design with a steampunk twist. Furthermore, to achieve compatibility across a range of devices, [Zack’s] CAD model is the result of adjusting for various meter profiles from images he snapped in the urban wilderness. The result? A clean, authentic piece of equipment compatible with a family of meters.
For the shrewd-eyed observers, [Zack’s] first video post arrived online in 2011, but his work later resurfaced at a presentation in the 2015 Tangible, Embedded, and Embodied Conference by his former design instructor [Eric Paulos], who was eager to show off [Zack’s] work. For a deeper dive into the upcoming second edition, head on over to [Zack’s] image feed.
Continue reading “Auto-Meter Reader Feeder Keeps Meter-Maids at Bay”
[Ramon] was always fascinated with pianos, and when he came across a few player piano rolls in an antique shop, a small kernel of a project idea was formed. He wondered if anyone had ever tried to convert a player piano into a full MIDI instrument, with a computer tickling the ivories with a few commands. This led to one of the best builds we’ve ever seen: a player piano connected to a computer.
[Ramon] found an old piano in Craigslist for a few hundred dollars, and once it made its way into the workshop the teardown began. Player pianos work via a vacuum, where air is sucked through a few pin points in a piano roll with a bellows. A series of pipes leading to each key translate these small holes into notes. Replicating this system for a MIDI device would be impossible, but there are a few companies that make electronic adapters for player pianos. All [Ramon] would have to do is replicate that.
The lead pipes were torn out and replaced with 88 separate solenoid valves. These valves are controlled via a shift register, and the shift registers controlled by an ATMega. There’s an astonishing amount of electronic and mechanical work invested in this build, and the finished product shows that.
As if turning an ancient player piano into something that can understand and play MIDI music wasn’t enough, [Ramon] decided to add a few visuals to the mix. He found a display with a ratio of 16:4.5 – yes, half as tall as 16:9 – and turned the front of the piano into a giant display. The ten different styles of visualization were whipped up in Processing.
The piano has so far been shown at an interactive art exhibit in Oakland, and hopefully it’ll make it to one of the Maker Faires next year. There are also plans to have this piano output MIDI with a key scanner underneath all the keys. Very impressive work.
Continue reading “Making a Player Piano Talk MIDI”